Stretching device for fibrous sheet material



July 17, 1956 H. HEITMULLER ET AL STRETCHING DEVICE FOR FIBROUS SHEET MATERIAL Filed Feb. 27, 1953 4 Sheets-Sheet l INVE/VTUPS.

HAHFRIED HE/Tmi/LLE AND '60 ETRICH' July 17, 1956 Filed Feb.

HEITMULLER ET AL 2,754,548

STRETCHING DEVICE FOR FIBROUS SHEET MATERIAL 27, 1953 4 Sheets-Sheet 2 Wyn/r025 HAHFRIED HEITmULLE AND )Go ETfi/ch' J ly 7, 1956 H. HEITMULLER ET AL 2,754,548

STRETCHING DEVICE FOR FIBROUS SHEET MATERIAL.

Filed Feb. 27, 1955 4 Sheets-Sheet 3 MIKE/V7095 HANFRIED Hen-MULLE MD Ic'o ETRICH BY.

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STRETCHING DEVICE FOR FIBROUS SHEET MATERIAL Filed Feb. 27, 1955 July 17, 1956 H. HEITMULLER ET AL 4 Sheets-Sheet 4 l/WA/IORS.

HAHFR ED Han-mm AND I60 ET FIG 70 ulnnnnnnu RICH United States Patent STRETCHING DEVICE FORIFIBROUS SHEET MATERIAL Hanfried Heitmiiller, Hamburg-Bergedorf, and Igo Etrich, Freilassing, Bavaria,'Germany Application February 27,1953, SerialNo. 339,278

Claims priority,.application'Germany AugustS, 1950 8 Claims. (Cl. 19-127) The present invention relates to a stretching device for fibrous sheet material and more particularly to a needle stretching device in which two pairs of chains carrying needle supporting'rods, are arranged on both sides of the sheet material.

It is the object of the present invention to provlde in a device of this type a chain drive permitting a high speed of operation.

It is another object of the present invention to provide the chains carrying the needle supporting rods with toothed chain links-pivoted to each other.

it is a further object of the present invention to mount the needle supporting rods turnable in bearings of the chain links which are outwardly spaced from the pivoting points of the chain links.

It is a still further-object "of the present invention to provide means for pivoting the needle supporting rods during operation so that the needles on the same are turned to a position normal 'to the-sheet material before entering the same, and While leaving the same.

it is still another object of the present invention to provide means for relative adjustment between the'two pairs of cooperating chains.

It is yet another object of the present "invention to mount one pair of chains on a pivoted supportso as to permit access to the sheet material.

With these objects in view-the present invention mainly consists in a stretching device for fibrous sheet material comprising at least one pair-of transversely spaced endless chains, drive means for driving the chains and a plurality of needle supporting rods extending in transverse direction between the chains and being'mounted-in the same.

Each needle supporting'rod carries a row of needles and is turnably mounted in opposite links-ofthe chains. According to a-preferred embodiment of the present invention, the end portions of the needle supporting rods areformed as cranks and areguided in cam=tracks which deviate from the path of the endless chains so that, during movement of :the chains, the needle supporting rods are turned in such manner sothat the needleszon thesame extend normal to the sheet material while-entering and leaving the sheet material.

This arrangement is particularly advantageous in a double needle stretching device in which the needles project from both sides into the sheet material.

Preferably the needle supporting rods are mounted intermediate and outwardly of the pivoting points of pivotally connected chain link-swhieh are providedwithinner teeth meshing with the chain Wheels which support the chains to form endless parallel loops.

This arrangement results in 'a wider spacing between the needle supporting rods when the -same pass around the rollers, while the needles are more closely spacedon straight portions ofthe chains, and permits a very narrow gap between the needle rods and the output pressure rollers which pull the sheet material.

4 2,754,548 Patented July .17, 1955 Preferably the chain links consist of several lamellae permitting avery high speed of the chains.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its metheod-of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

Fig. l is a schematic, partly sectional, side view of a machine according to the present invention;

Fig. 2 is an isometric view of the machine;

Fig. 3 is a sectional view showing the arrangement of the needle supporting rods;

Fig. 4 is a sectional view of a chain;

Fig. 5 is a side view illustrating a cam track for turning the needle supporting rods;

Fig. 6 is a fragmentary plan view of a detail of a modifiedembodiment of a needle supporting rod;

Fig. 7 is a side view of a needle supporting rod accordingito Fig. '6;

Fig. 8 is a sectional view of apreferred embodiment of .thex'present invention;

Fig. 9 is a side view showing a detail of a machine according to the present invention; and

Fig' 10-is a side view similar to Fig. 9 showing a different .position.

Referring now to the drawings and more particularly to Fig. l, the fibrous sheet material, not shown, is held bythe input pressure rollers 1 and 2 and the output presice ' sure rollers 3 and 4 and extends in a working plane defined by the same. The roller pair 3, 4 pulls the sheet material in the direction of the arrow. Behind the rollers 3, 4a receiving plate 10 is arranged for guiding the sheet material to the delivery rollers 11, 12. The input pressure rollers 1, 2 include the driven roller 1, and the pressure roller 2 which is pressed against roller 1 by means of a lever system 13, 14 and 15 actuated by a weight 16. The rollers 1 and 2 are positively connected by gear means.

In the illustrated embodiment of thepresent invention, two pairs of chains 28, 19, are respectively arranged above and below the sheet material. The needle supporting rods 17, and the needle supporting rods 13 are mounted in the chain links of the lower and upper chains, respectively, and areprovided with needles projecting in radial direction. The lower chains 19 are guided over rollers 20, 21, .2-2 and 23, while the upper chains 28 are guided .overrollers 24, 25, 26 and 27. The chain wheels or rollers 20 and 24, respectively, drive the chains, while the rollers 23 and .27 are adjustable for tensioning the chains.

In order to permit a very narrow gap between the needle supporting rods 17, Band the rollers 3 and 4, the rollers 21 and 25 are preferably of small diameter and have a smooth surface permitting a sharp turn of the chains and needle supporting rods.

The rollers 25 and 26, and 21 and 22, respectively, are arranged in the working plane defined by the rollers 1, 2 and 3, 4. The needles 5 and 7 extend normal to the sheet material and project into the same when the needle supporting .rodsmove along .the straight portions 6 and 3 of thechains .19, .28.

The chains 19 .and 28 aretcomposed-of chain links 29, whichconsist of several parallel .lamellae 39, as can be best seen from'Eigs..3.and.6. The .chain links are toothed at the inner .portions .whichjpass over the chain rollers, each link having .two teeth 31. Adjacent chain links are staggered, the lamellae .of eachchainllink projecting into thespaces .betweenthe lamellae ,of the adjacent chain links, each .two adjacent chain links 29 being connected by transverse pins 32 permitting a relative pivoting of the chain links. The distance between the pivoting pins 32 should be as small as possible. Each chain link is formed with a bore 33 intermediate the associated pivoting pins 32 and located outwardly with respect to the same preferably on the line of symmetry extending perpendicular to the line connecting the pivot pins. The bores 33 of each second link are provided with assembly slots 35 having a width a, permitting an easy assembly of the needle supporting rods 17 which are formed with flattened portions 36 and 36' having the width a. The needle supporting rods are inserted with the flat portions passing through the slots 35 whereupon the needle supporting rods are shifted into their correct position in which the bearing portions of the needle rods are located in the bore 33. The needle supporting rods can be inserted with the portion 36' passing through the slot 35, whereupon the needle rods are shifted in axial direction.

As shown in Fig. 3, the needle supporting rods 17 are mounted on spaced bearing portions in the chain 19. Only every second chain link needs to be provided with a slot 35 since one end of the needle supporting rods can be pushed into the bearing holes 33 when the needle supporting rod is shifted.

The needle supporting rods 17, 18 are provided at least at one of their ends with cranks 37 on which small rollers 38 are rotatably mounted. As shown in Fig. 5, the rollers 38, or the ends of the cranks 37 are guided in cam track means 39 which are arranged adjacent to each chain. The cam tracks 39 deviate from the path defined by the chain loops so that the cranks 37 force the needle supporting rods to turn at predetermined places.

As can be seen from Fig. 2, the arrangement is such that the needles passing the input roller means 1, 2 and entering the sheet material are turned into a position in which they extend normal to the working plane before they arrive in the same so that the needles are entered into the sheet in a direction normal thereto. Tearing of the sheet is thereby prevented since the needle point, and not the side of the needle enters the sheet first. In a similar manner the cam tracks 39 force through the cranks 37 the needle supporting rods to turn when the needles leave the sheet in such manner that the needles are retracted in a direction normal to the working plane preventing tearing of the sheet and permitting a very short distance between the rollers 3 and 31, which is highly advantageous. It is evident that the cam tracks 39 will turn the needle supporting rods in an opposite direction while the needles pass from roller 3 back to roller 1.

The arrangement of the cranks 37 arranged on every second needle supporting rod on both sides of the chains 19, and the provision of two cam tracks 39 permits a closer spacing of the needle supporting rods. In order to obtain favorable sliding angles of the crank 37 in the cam track 39 it is advantageous to substitute for the simple cranks of Fig. 3 double cranks 40 as shown in Figs. 6 and 7.

Since the pivotal connections 32 are not located in the plane defined by the needle supporting rods 17 and 18 when the chains 19, 28 extend in the working plane, the distance t1 between the needle supporting rods passing about a roller is greater than the distance 2 on a straight portion of the chains which facilitates the turning of the needle supporting rods by the cam tracks as described above.

Referring now to Figs. 1, 9 and 10, the upper chains 28 and the rollers 24, 25, 26 and 27 are mounted in a supporting casing 41 which is pivotally mounted on a hinge pin 42 and can be moved between a closed position shown in Fig. 9 and an open position shown in Fig. 10. The fibrous sheet material is inserted in the open position of Fig. 10, which also permits exchange of needle supporting rods and inspection of the sheet material during operation.

The upper chains 28 move at the same speed as the lower chains 19. The drive shaft 43, on which the chain driving roller 20 is fixedly mounted, is connected by means of the bevel gears 44, 45 to an expandable shaft means 46 which drives through the bevel gears 47, 48 the drive shaft 49 of the upper chains 28 on which the chain drive roller 24 is fixedly mounted. The expandable shaft 46 is preferably composed of a tubular member provided with longitudinal inner grooves in which a shaft is keyed so as to be non-rotatable and slidable in axial direction. Other means may be provided for connecting the inner shaft to the outer tube non-rotatable but axially slidable.

As shown in Fig. 9, the bevel gears 44 and 45, and 47 and 48, roll on each other when the supporting casing 41 is pivoted while the driving connection through the motion transmitting means 44 to 48 is maintained. The bearings 50 and 51 in which the two parts of the expandable shaft 46 are rotatably mounted, are turnably arranged on the shafts 43, 49 of the chain rollers 20, 24. Consequently the shafts 49 and 43 do not rotate when the shaft 46 is turned about the angle a due to the opposite arrangement of the bevel gears 45, 47. Therefore the position of the lower needles 5 remains the same as regards the upper needles 7 so that the upper needles 7 can be moved from their operative position projecting between the needles 5 to an inoperative position by pivoting the supporting casing 41 to the position shown in Fig. 10, and back again, during operation of the machine.

It is desirable to change the relative position between the lower needles 5 and the upper needles 7 in certain conditions.

For this purpose an adjusting means is provided at the upper end of the shaft 46. The bevel gear 47 is not fixedly secured to the shaft 46, but connected thereto by means of a self-locking worm 52 meshing with a worm gear 53 which is fixedly connected to the shaft 46. By turning the worm 52, the position of the bevel gear 47 and of bevel gear 48, the position of the upper needles 7 with respect to the lower needle 5 can be adjusted. Other adjusting means such as a clamping arrangement, or an adjustable coupling may be used.

The pulling roller pair 3, 4 includes the pulling roller 3 and the pressure roller 4. The latter may be subdivided into several cylindrical rollers if the machine is very wide. In the embodiment shown in Fig. 2 two cylinderical rollers 4 are provided.

In order to prevent a stopping and accumulating of the material at the roller pair 3, 4, the pressure roller 4 is not frictionally driven from the roller 3, but positively driven by the same by gear means. The pressure roller 4 is pressed against the roller 3 by a weight 57 acting through lever means 54, 55 and 56. The lever system is arranged in such manner that the two pressure cylinders 4 can be independently lifted. The pressure rollers 4 are rotatably mounted and are adjustable about small angles with respect to the longitudinal roller axis for equalizing variations in the thickness of the sheet material.

The delivery rollers 11, 12 include the driven roller 11 and the pressure roller 12 which is pressed by springs 61 against the roller 11. The pressure roller 12 is driven positively from the roller 11.

In order to prevent a deposit of dust and fiber particles on the needles, which would result in an excessive wear of the chains 19, 28 and of the crank 37 and cam track 39, these parts are tightly covered by cover means 58. The space within the cover means 58 is filled with compressed air which is produced by a fan 59. The compressed air leaves the protected spaces through slots through which the needle supporting rods 17 and 18 enter and thereby prevents the entering of dust and fibers. The compressed air is admitted into the closed spaces through openings 60.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of needle stretching devices for fibrous sheet material differing from the types described above.

While the invention hasbeen illustrated and described as embodied in an operating arrangement for a double needle stretching device, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What .is claimed as new and desired to be secured by Letters Patent is:

1. In a textile machine of the type described, in combination, at least one pair of transversely spaced endless chains, each chain including a plurality of pivotally connected chain links, at least every second chain link being formed with a bearing bore located outwardly of the pivoting points of said chain links, and being further formed with assembly slots connecting said bearing bores with the periphery of said chain links and having a predetermined width smaller than the diameter of said hearing bores; roller means supporting said chains to form parallel loops; drive means for driving said chains; and a plurality of needle supporting rods extending in transverse directions between said chains, each needle supporting rod having spaced bearing portions turnably supported in opposite chain links of said spaced chains in said bearing bores, said needle supporting rods being formed with flattened portions having a thickness corresponding to said width of said slots for inserting said needle supporting rods through said assembly slots in an axially shifted position of said rods.

2. In a device of the type described, in combination, a pair of input pressure rollers and a pair of output pressure rollers defining a working plane for a sheet material; two pairs of endless chains, each pair of chains being arranged intermediate said input and output pressure rollers on one side of said working plane; drive means for driving said pairs of chains, said drive means including an expandable shaft means; two sets of roller means supporting said pairs of chains, each set of roller means including at least two spaced rollers guiding portions of the associated pairs of chains in said working plane; movable supporting means supporting the one set of roller means supporting one of said pairs of chains and being movable to a position in which said one pair of chains is spaced from the other pair of chains so as to permit access to said working plane and to said sheet material, said expandable shaft means being expanded during such movement; a plurality of needle supporting rods extending in transverse direction between said chains of each pair of chains, each needle supporting rod having spaced bearing portions turnably supported in opposite chain links; and a row of needles on each of said needle supporting rods projecting radially from the same, said needle supporting rods being mounted in said chains in such manner that said needles project from both sides normal to and into said working plane.

3. In a device of the type described, in combination, a pair of input pressure rollers and a pair of output pressure rollers defining a working plane for a sheet material; two pairs of endless toothed chains, each pair of chains being arranged intermediate said input and output pressure rollers on one side of said working plane; drive means for driving said pairs of chains; two sets of roller means supporting said pairs of chains, each set of roller means including at least two spaced rollers guiding portions of the associated pairs of chains in said working plane, each set of roller means including at least one pair of toothed chain rollers meshing with said chains, at least one pair of toothed chain rollers being driven by said driving means; motion transmitting means connecting said one pair of toothed chain rollers associated with one pair of chains with the other pair of toothed chain rollers associated with the other pair of chains, said motion transmitting means including worm gear means permitting adjustment of the relative position between said pairs of toothed chain rollers; a plurality of needle supporting rods extending in transverse direction between said chains of each pair of chains, each needle supporting rod having spaced bearing portions turnably supported in opposite chain links; and a row of needles on each of said needle supporting rods projecting radially from the same, said needle supporting rods being mounted in said chains in such manner that said needles project from both sides normal to and into said working plane.

4. In a device of the type described, in combination, a pair of input pressure rollers and a pair of output pressure rollers defining a working plane for a sheet material; two pairs of endless toothed chains, each pair of chains being arranged intermediate said input and output pressure rollers on one side of said working plane; drive means for driving said pairs of chains; two sets of roller means supporting said pairs of chains, each set of roller means including at least two spaced rollers guiding portions of the associated pairs of chains in said working plane, each set of roller means including at least one pair of toothed chain rollers meshing with said chains, at least one pair of toothed chain rollers being driven by said driving means; motion transmitting means connecting said one pair of toothed chain rollers associated with one pair of chains with the other pair of toothed chain rollers associated with the other pair of chains, said motion transmitting means including an expandable shaft means and worm gear means permitting adjustment of the relative position between said pairs of toothed chain rollers; movable supporting means supporting the one set of roller means supporting one of said pairs of chains and being movable to a position in which said one pair of chains is spaced from the other pair of chains so as to permit access to said working plane and to said sheet material, said expandable shaft means being expanded during such movement; a plurality of needle supporting rods extending in transverse direction between said chains of each pair of chains, each needle supporting rod having spaced bearing portions turnably supported in opposite chain links; and a row of needles on each of said needle supporting rods projecting radially from the same, said needle supporting rods being mounted in said chains in such manner that said needles project from both sides normal to and into said working plane.

5. A device as claimed in claim 2 and including cover means enclosing said chains and said roller means and being formed with slots for passing of said needle supporting rods into said casing means during movement of said chains; and fan means communicating with the space within said cover means for supplying compressed air to the same.

6. In a device of the type described, in combination, a pair of input pressure rollers and a pair of output pressure rollers defining a working plane for a sheet material; two pairs of endless chains, each pair of chains being arranged intermediate said input and output pressure rollers on one side of said working plane; first and second drive means for driving said pairs of chains, respectively; means for synchronizing said first and second drive means; two sets of roller means supporting said pairs of chains, each set of roller means including at least two spaced rollers guiding portions of the associated pairs of chains in said working plane; movable supporting means supporting the one set of roller means supporting one of said pairs of chains and being movable to a position in which said one pair of chains is spaced from the other pair of chains so as to permit access to said working plane and to said sheet material; a plurality of needle supporting rods extending in transverse direction between said chains of each pair of chains, each needle supporting rod having spaced bearing portions turnabiy supported in opposite chain links; and a row of needles on each of said needle supporting rods projecting radially from the same, said needle supporting rods being mounted in said chains in such manner that said needles project from both sides normal to and into said working plane.

7. A device as claimed in claim 1 and including cover means enclosing said chains and said roller means and being formed with slots for passing of said needle supporting rods into said casing means during movement of said chains; and fan means communicating with the space within said cover means for supplying compressed air to the same.

8. In a textile machine, in combination, a pair of transversely spaced cndlcss chains, each chain including a plurality of pivotally connected chain links, each chain link being composed of a plurality of toothed lamellae; drive means for driving said pair of chains; a plurality of needle supporting rods extending in transverse direction between the chains of said pair of chains and being mounted in the same; input and output pressure rollers spaced along the length of said chains for defining a working plane for a sheet material; and roller means supporting said chains to form parallel loops and including two longitudinally spaced pairs of transversely spaced rollers located between said input and output pressure rollers adjacent said working plane and guiding portions of said chains to move in in a plane parallel to said working plane, the one pair of said transversely spaced rollers located adjacent said output pressure rollers being smooth and having a small diameter so as to guide said chains and said needle supporting rods to make a sharp turn when passing between said one pair of transversely spaced rollers and said output rollers, and the other pair of said transversely spaced rollers being a pair of toothed chain sprockets respectively meshing with said toothed lamellae of said chains.

References Cited in the file of this patent UNITED STATES PATENTS 443,999 Lawson et a1. Jan. 6, 1891 781,892 Mann Feb. 7, 1905 1,956,942 Belcher et a1 May 1, 1934 2,111,925 Eves Mar. 22, 1938 FOREIGN PATENTS 4,016 Great Britain of 1874 4,017 Great Britain of 1874 481,304 Great Britain Mar. 9, 1938 

